Cocker spaniel

[alyssa2590]

How long does a dogs heat cycle usually last?

[Ghilly]

A dog's heat cycle lasts approximately 21 days, however the dog isn't fertile for the whole cycle.  She is actually only fertile for 24 hours during her entire heat cycle, but because the male dog's sperm is able to live inside her after she is bred for up to three days, she has a window of opportunity there to get pregnant even if she is bred before her fertile time arrives.

For the first five to seven days, the dog will be spotting blood.  During this time she isn't fertile, and she will probably go after any males who show an interest in her because even though she smells very good to them at this time, she's still not fertile, so she's not interested in breeding.

There have been incidents of females getting bred on day 23 of their cycle, so it's not a hard and fast rule that after 21 days it is safe to let her be around males again.  Keep an eye on the swelling of her vulva.  When the swelling goes down, and the vulva returns to its normal size, it's safe to allow her to be around males again.

The safest thing to do, if you do not plan to show your dog, is to have her spayed ASAP.  If you have her spayed, it greatly reduces her chances of developing mammary cancer, and it COMPLETELY removes any chance of her developing pyometra, which is a life-threatening infection of the uterus.  

Ghilly

[kitty51]

21 days is the usual cycle,if you dont like the mess yo can get a dog conraceptive that will stop it.

[Jaybay]

It's kind of like humans - a couple days to a week.  Is your dog having a particular problem?